I thought I'd be smart and have my radiator (82 westy diesel, now gas
powered), cleaned/boiled in acid/base and checked for leaks. I flushed the
system last summer and noticed that the inside of the rad looked grungy,
so before the hot?! weather set in, it seemed prudent to have the cooling
system perked up (besides, the temp guage has recently moved to the right
about one needle width, turning on the heat brought it back to the middle). 
Last evening I drained the system, checked the thermostat (87 C, German
going to change to a 80 C Brazilian, is this a smart move?), then went
forrard to remove grill, fan temp senders, spare tire cover and wire
things that are accused of causing squeeks on other vans, detached big
hose from bottom, and hose from top near bleed screw, 2 nuts up top and 4
bolts from below removed and the whole rad + fan gently fell down and out.
It is quite an easy job except for the collection and disposal of the coolant.
Took the rad to a shop today, where they tried to boil (twice) out the
crude but got no increase in flow and I guess during this process a tube
split. So I have to get a new core...it will be made-up in Vancouver this
afternoon and sent overnight to Victoria where the end caps etc will be
soldered on and the whole thing painted. Its going to cost Can$275! I
thought that this was expensive until, just out of curiosity, I called VW
to find out that a new one costs Can$799.97!!!
My van does have 105K miles on it, so I guess these things will happen.
Whilst the rad is in the shop, I'm going to have a 5" length of 1/4"
copper tubing soldered to the outside right hand edge so that I can
connect my windshield fluid hose and have hot/warm fluid.

Alistair